11.1.7. Reverting to Normal Operation 
When a HG 3575/virtual HG 3575 discovers that the signaling connection
to the central control unit has been restored, it reports this event
to the allocated survivability unit.
The survivability unit uses preconfigured rules to decide whether
or not it should hand back access point/OpenScape 4000 SoftGate control
to the host system.
- Every access point/OpenScape 4000 SoftGate in an emergency group must
have a stable connection to the host system for a minimum set time
- Automatic reversion is only permitted during a set interval during the day. The interval can be set to 24 hours so that automatic reversion is possible at any time.
- Automatic reversion can be deactivated.
- You can also switch back control of
- individual access points/OpenScape 4000 SoftGates,
- all access points/OpenScape 4000 SoftGates in an emergency group,
- all access points/OpenScape 4000 SoftGates in all emergency groups in a survivability unit or
- all access points/OpenScape 4000 SoftGates in the entire OpenScape 4000 system
to the central control unit at any time.The survivability unit returns access point/OpenScape 4000 SoftGate control to the central control unit by instructing the HG 3575/virtual HG 3575 to initiate a restart and then start up with the central control unit. The HG 3575/virtual HG 3575 restart triggers a restart in all peripheral boards on the access point/OpenScape 4000 SoftGate. - All calls are cleared down.
- Features with active logon, e.g. mobile subscribers (PIN, mobile HFA), are logged off.
- Features that can be configured by the user, such as key layout (name keys, DSS keys), forwarding key, reminder key, etc., are set up in the state which is active in the host system - i.e. generally as it was prior to switchover.